Activity at the hive entrance, hive occupancy and worker survival were monitored in two spraying operations involving 10 spray cycles and application rates of 10-41 g active ingredient ha-1. Applications of 15-41 g ha-1 caused hyperactivity and some colonies probably deserted their hives. Sprays of 10-24 g ha-1 had no immediate effect on survival, but mortality increased after sprays of 28-41 g ha-1. Foraging by workers before sunrise, when spraying ended, and the greater toxicity of endosulfan at high temperatures, may have increased the hazard of endosulfan drift sprays to honeybees in Somalia.

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